Got it. This file was exported with older version of URE Pro. It’s format is not compatible with versions of URE Pro starting from 4.41:

= [4.41] 06.02.2018 =
* Core version: 4.40.1
* New: Export-import module was rewritten:
* - Attention: New exported data format is not compatible with data exported by older versions.
* - Users->User Role Editor: Export/Import buttons applied to the single currently selected role only.